Dynamoelectric machine

Abstract

In an electric motor (11) with at least one winding (14) through which an electric current flows to produce a relative movement between a stator portion and a reaction portion, with at least one magnet (12), the field of which passes through the winding, and with at least one body (20) of ferromagnetic material which is arranged in the fields of the magnet and winding in order to achieve the minimum structural configuration with the maximum outputtable force, it is provided that the winding is immovably connected to the magnet at least in the direction of the relative movement and that the body of ferromagnetic material is mounted movably relative to the winding and the magnet in the direction of the relative movement, and has an air gap (22) which extends transversely to said direction of relative movement and which is so arranged that the magnetic flux in the winding alters as a result of the relative movement of the air gap with respect to the winding and the magnet.

What is claimed is: 
     
       1. A rotary electrical machine comprising a stator portion, a rotor portion, and mounting means adapted to permit a relative rotary movement therebetween, wherein said stator portion includes   a winding arrangement consisting of first and second windings which are adapted to be actuated in the same sense and each of which is in the form of a coil enclosing a continuous internal space,   means for a flow of electrical current through the winding arrangement in operation of the machine,   wherein said rotor portion includes   a core means in the form of an elongate body which at least partially comprises ferromagnetic material, and is common to both windings by extending through the internal spaces surrounded by them, said windings being arranged at a spacing from each other in the longitudinal direction of the core means,   wherein said stator portion further includes   a magnet arrangement consisting of first and second magnets which are arranged in mutually opposite relationship with respect to the longitudinal axis of said core means in the spacing between said first and second windings, each of said first and second magnets partially embracing said core means, and at any time in operation of the machine the magnetization direction of at least one magnet being directed from the outside towards the core means whilst that of at least one magnet being directed from the core means outwardly,   said winding arrangement and said magnet arrangement being mounted immovably with respect to each other at least in the direction of said relative linear movement, and said core means being mounted rotatably around its longitudinal axis with respect to said magnet arrangement and said winding arrangement, the flux of said magnet arrangement passing through the peripheral surface of the core means transversely to the longitudinal direction of the latter and being deflected in the interior of said core means in the longitudinal direction thereof,   said core means having at least one gap which extends with a direction component which is transverse with respect to the longitudinal direction of the core means and also a direction component which is in the longitudinal direction of the core means, said gap being filled with material of low magnetic permeability, so that by virtue of its relative rotary movement with respect to said winding and magnet arrangements the magnetic flux in the winding arrangement alters.   
     
     
       2. A machine as set forth in claim 1 wherein said gap extends in the longitudinal direction of the core means to such an extent that in the assembled condition it bridges over the axial spacing between said first and second windings. 
     
     
       3. A machine as set forth in claim 2, wherein the windings and the magnet arrangement are each in the form of a straight hollow cylinder with circular inside and outside cross-sections and are so arranged that their longitudinal axes are aligned with each other. 
     
     
       4. A machine as set forth in claim 1 and further including at least one further magnet which covers only a small part of the periphery of the core means and means for switching over the direction of magnetization of said further magnet in such a way that it corresponds selectively to the magnetization direction of the one of said first and second magnets or the direction of magnetization of the other of said first and second magnets. 
     
     
       5. A machine as set forth in claim 1 and further including: a casing means in the form of an elongate body which at least partially comprises ferromagnetic material and which surrounds the winding and magnet arrangements from the outside so that its longitudinal axis is at least substantially parallel to the longitudinal axes of said winding and magnet arrangements, and at least first and second yokes of ferromagnetic material and of such a configuration and arrangement that with the casing means they form a return path arrangement of defined magnetic resistance for the magnetic flux which passes through the core means. 
     
     
       6. A machine as set forth in claim 5 wherein said yokes are fixedly connected to the casing means and the casing means is connected to the assembly comprising the winding arrangement and the magnet arrangement immovably at least in the direction of said relative rotary movement, wherein further the yokes have continuous openings in the longitudinal direction, which permit a relative rotary movement of the core means which passes through them, the gaps between the core means and the yokes forming a lower level of magnetic resistance than the gap which passes through the core means. 
     
     
       7. A machine as set forth in claim 1 wherein said at least one gap in the core means is filled with a solid material of low magnetic permeability, which with parts of the core means which are of ferromagnetic material forms an overall body with continuous external contures. 
     
     
       8. A machine as set forth in claim 1 in the form of an electrical motor. 
     
     
       9. An electrical motor assembly comprising at least first and second electrical motors as set forth in claim 8 including means for connecting all the winding and magnet arrangements together immovably at least in the direction of the relative rotary movement, wherein said core means which at least partially comprises ferromagnetic material is common to the motors, the core means having a gap for each motor, and means for actuating the winding arrangements such that the forces occurring between the winding and magnet arrangements of each motor and the common core means act in the same direction to produce a relative rotary movement. 
     
     
       10. An assembly as set forth in claim 9, including a casing common to the electrical motors and including a plurality of yoke means of which at least one is associated with the first and second electrical motors. 
     
     
       11. A machine as set forth in claim 1 wherein said magnet arrangement is formed by permanent magnet means. 
     
     
       12. A machine as set forth in claim 1 wherein the thickness of material and shape of the core, the yoke means and the casing means in the various cross-sectional regions are so matched to the magnetic flux which passes through the respective cross-sectional region at the maximum that saturation is avoided with the minimum requirement of material. 
     
     
       13. An electrical machine as set forth in claim 1 in the form of an electrical generator. 
     
     
       14. A linear electrical machine comprising a stator portion, a reaction portion, and mounting means adapted to permit a relative movement therebetween, wherein said stator portion includes a winding arrangement consisting of at least one winding in the form of an elongate hollow body having a continuous internal space,   means for a flow of electrical current through the winding arrangement in operation of the machine,   a magnet arrangement consisting of at least one magnet in the form of an elongate hollow body, the direction of magnetization of which extends at least substantially perpendicularly to its longitudinal axis, and which encloses a continuous internal space,   said winding arrangement and said magnet arrangement being mounted immovably with respect to each other at least in the direction of said relative linear movement,   one of said winding and magnet arrangements concentrically surrounding the respective other arrangement so that the longitudinal axis of the magnet arrangement extends at least substantially parallel to the longitudinal axis of the winding arrangement, whereby the field of said magnet arrangement passes through said winding arrangement, and wherein said reaction portion includes   a core means in the form of an elongate body which at least partially comprises ferromagnetic material, and extends through a hollow space surrounded by said winding and magnet arrangements so that its longitudinal axis is at least substantially parallel to the longitudinal axes of said winding and magnet arrangements, said core means being mounted movably with respect to said winding and magnet arrangements in its longitudinal direction for said relative linear movement, and having at least one gap which extends transversely with respect to said direction and is filled with material of low magnetic permeability and is so arranged that by virtue of its relative linear movement with respect to the winding and magnet arrangements the magnetic flux generated by the magnet arrangement as well as the magnetic flux generated by the winding arrangement changes its direction in the region where it passes through said core means.   
     
     
       15. A machine as set forth in claim 14 wherein said stator portion further includes: a casing means in the form of an elongate body which at least partially comprises ferromagnetic material and which surrounds the winding and magnet arrangements from the outside so that its longitudinal axis is at least substantially parallel to the longitudinal axes of said winding and magnet arrangements, and at least first and second yokes of ferromagnetic material and of such a configuration and arrangement that with the casing means they form a return path arrangement of defined magnetic resistance for the magnetic flux which passes through the core means. 
     
     
       16. A machine as set forth in claim 15 wherein said yokes are fixedly connected to the casing means and the casing means is connected to the assembly comprising the winding arrangement and the magnet arrangement immovably at least in the direction of said relative linear movement, wherein further the yokes have continuous openings in the longitudinal direction, which permit a relative movement of the core means which passes through them, the gaps between the core means and the yokes forming a lower level of magnetic resistance than the gap which passes through the core means. 
     
     
       17. A machine as set forth in claim 14 wherein said at least one gap in the core means is filled with a solid material of low magnetic permeability, which with parts of the core means which are of ferromagnetic material forms an overall body with continuous external contures. 
     
     
       18. A machine as set forth in claim 14 in the form of an electrical motor. 
     
     
       19. An electrical motor assembly comprising at least first and second electrical motors as set forth in claim 18 including means for connecting all the winding and magnet arrangements together immovably at least in the direction of the relative linear movement, wherein said core means which at least partially comprises ferromagnetic material is common to the motors, the core means having a gap for each motor, and means for actuating the winding arrangements such that the forces occurring between the winding and magnet arrangements of each motor and the common core means act in the same direction to produce a relative linear movement. 
     
     
       20. An assembly as set forth in claim 19, including a casing common to the electrical motors and including a plurality of yoke means of which at least one is associated with the first and second electrical motors. 
     
     
       21. A linear electrical machine comprising a stator portion, a reaction portion, and mounting means adapted to permit a relative movement therebetween, wherein said reaction portion includes a winding arrangement consisting of at least one winding in the form of an elongate hollow body having a continuous internal space,   means for a flow of electrical current through the winding arrangement in operation of the machine,   a magnet arrangement consisting of at least one magnet in the form of an elongate hollow body, the direction of magnetization of which extends at least substantially perpendicularly to its longitudinal axis, and which encloses a continuous internal space,   said winding arrangement and said magnet arrangement being mounted immovably with respect to each other at least in the direction of said relative linear movement,   one of said winding and magnet arrangements concentrically surrounding the respective other arrangement so that the longitudinal axis of the magnet arrangement extends at least substantially parallel to the longitudinal axis of the winding arrangement, whereby the field of said magnet arrangement passes through said winding arrangement, and wherein said stator portion includes   a core means in the form of an elongate body which at least partially comprises ferromagnetic material, and extends through a hollow space surrounded by said winding and magnet arrangements so that its longitudinal axis is at least substantially parallel to the longitudinal axes of said winding and magnet arrangements, said core means being mounted movably with respect to said winding and magnet arrangements in its longitudinal direction for said relative linear movement, and having at least one gap which extends transversely with respect to said direction and is filled with material of low magnetic permeability and is so arranged that by virtue of its relative linear movement with respect to the winding and magnet arrangements the magnetic flux generated by the magnet arrangement as well as the magnetic flux generated by the winding arrangement changes its direction in the region where it passes through said core means.   
     
     
       22. A machine as set forth in claim 21 wherein said reaction portion further includes: a casing means in the form of an elongate body which at least partially comprises ferromagnetic material and which surrounds the winding and magnet arrangements from the outside so that its longitudinal axis is at least substantially parallel to the longitudinal axes of said winding and magnet arrangements, and at least first and second yokes of ferromagnetic material and of such a configuration and arrangement that with the casing means they form a return path arrangement of defined magnetic resistance for the magnetic flux which passes through the core means. 
     
     
       23. A machine as set forth in claim 22 wherein said yokes are fixedly connected to the casing means and the casing means is connected to the assembly comprising the winding arrangement and the magnet arrangement immovably at least in the direction of said relative linear movement, wherein further the yokes have continuous openings in the longitudinal direction, which permit a relative movement of the core means which passes through them, the gaps between the core means and the yokes forming a lower level of magnetic resistance than the gap which passes through the core means. 
     
     
       24. A machine as set forth in claim 21 wherein said at least one gap in the core means is filled with a solid material of low magnetic permeability, which with parts of the core means which are of ferromagnetic material forms an overall body with continuous external contures. 
     
     
       25. A machine as set forth in claim 21 in the form of an electrical motor. 
     
     
       26. An electrical motor assembly comprising at least first and second electrical motors as set forth in claim 25 including means for connecting all the winding and magnet arrangements together immovably at least in the direction of the relative linear movement, wherein said core means which at least partially comprises ferromagnetic material is common to the motors, the core means having a gap for each motor, and means for actuating the winding arrangements such that the forces occurring between the winding and magnet arrangements of each motor and the common core means act in the same direction to produce a relative linear movement. 
     
     
       27. An assembly as set forth in claim 26, including a casing common to the electrical motors and including a plurality of yoke means of which at least one is associated with the first and second electrical motors. 
     
     
       28. A linear electrical machine comprising a stator portion, a reaction portion, and mounting means adapted to permit a relative linear movement therebetween, wherein said stator portion includes a winding arrangement consisting of at least one winding in the form of an elongate hollow body having a continuous internal space,   means for a flow of electrical current through the winding in operation of the machine,   a magnet arrangement consisting of at least one magnet in the form of an elongate hollow body, the direction of magnetization of which extends at least substantially perpendicularly to its longitudinal axis, and which encloses a continuous internal space,   said winding arrangement and said magnet arrangement being mounted immovably with respect to each other at least in the direction of said relative linear movement,   one of said winding and magnet arrangements concentrically surrounding the respective other arrangement so that the longitudinal axis of the magnet arrangement extends at least substantially parallel to the longitudinal axis of the winding arrangement, whereby the field of said magnet arrangement passes through said winding arrangement, and wherein said reaction portion includes   a casing means in the form of an elongate body which at least partially comprises ferromagnetic material, and surrounds the winding and magnet arrangements from the outside so that its longitudinal axis is at least substantially parallel to the longitudinal axes of said winding and magnet arrangements, said casing means being mounted movably with respect to said winding and magnet arrangements in its longitudinal direction for said relative linear movement, and having at least one gap which extends transversely with respect to said direction and is filled with material of low magnetic permeability and is so arranged that by virtue of its relative linear movement with respect to the winding and magnet arrangements the magnetic flux generated by the magnet arrangement as well as the magnetic flux generated by the winding arrangement changes its direction in the region where it passes through said core means.   
     
     
       29. A machine as set forth in claim 28 wherein said stator portion further includes: a core means in the form of an elongate body which at least partially comprises ferromagnetic material and which extends through a hollow space surrounded by said winding and magnet arrangements so that its longitudinal axis is at least substantially parallel to the longitudinal axes of said winding and magnet arrangements, and at least first and second yokes of ferromagnetic material and of such a configuration and arrangement that with the core means they form a return path arrangement of defined magnetic resistance for the magnetic flux which passes through the casing means. 
     
     
       30. A machine as set forth in claim 29 wherein said yokes are fixedly connected to the core means and the core means is connected to the assembly comprising the winding arrangement and the magnet arrangement immovably at least in the direction of said relative linear movement, wherein further the casing means surrounds the yokes and is separated from them by gaps which permit a relative movement of the casing means and form a lower level of magnetic resistance than the gap which passes through the casing means. 
     
     
       31. A machine as set forth in claim 28 wherein that at least one gap in the casing means is filled with a solid material of low magnetic permeability, which with parts of the casing means which are of ferromagnetic material forms an overall body with continuous internal contures. 
     
     
       32. A machine as set forth in claim 28 in the form of an electrical motor. 
     
     
       33. An electrical motor assembly comprising at least first and second electrical motors as set forth in claim 32, including means for connecting all the winding and magnet arrangements together immovably at least in the direction of the relative linear movement, wherein said casing means which at least partially comprises ferromagnetic material is common to the motors, the casing means having a gap for each motor, and means for actuating the winding arrangements such that the forces occurring between the winding and magnet arrangements of each motor and the common casing means act in the same direction to produce a relative linear movement. 
     
     
       34. An assembly as set forth in claim 33 including a core common to the electrical motors and including a plurality of yoke means of which at least one is associated with the first and second electrical motors. 
     
     
       35. A linear electrical machine comprising a stator portion, a reaction portion, and mounting means adapted to permit a relative linear movement therebetween, wherein said reaction portion includes a winding arrangement consisting of at least one winding in the form of an elongate hollow body having a continuous internal space,   means for a flow of electrical current through the winding in operation of the machine,   a magnet arrangement consisting of at least one magnet in the form of an elongate hollow body, the direction of magnetization of which extends at least substantially perpendicularly to its longitudinal axis, and which encloses a continuous internal space,   said winding arrangement and said magnet arrangement being mounted immovably with respect to each other at least in the direction of said relative linear movement,   one of said winding and magnet arrangements concentrically surrounding the respective other arrangement so that the longitudinal axis of the magnet arrangement extends at least substantially parallel to the longitudinal axis of the winding arrangement, whereby the field of said magnet arrangement passes through said winding arrangement, and wherein said stator portion includes   a casing means in the form of an elongate body which at least partially comprises ferromagnetic material, and surrounds the winding and magnet arrangements from the outside so that its longitudinal axis is at least substantially parallel to the longitudinal axes of said winding and magnet arrangements, said casing means being mounted movably with respect to said winding and magnet arrangements in its longitudinal direction for said relative linear movement, and having at least one gap which extends transversely with respect to said direction and is filled with material of low magnetic permeability and is so arranged that by virtue of its relative linear movement with respect to the winding and magnet arrangements the magnetic flux generated by the magnet arrangement as well as the magnetic flux generated by the winding arrangement changes its direction in the region where it passes through said core means.   
     
     
       36. A machine as set forth in claim 35 wherein said reaction portion further includes: a core means in the form of an elongate body which at least partially comprises ferromagnetic material and which extends through a hollow space surrounded by said winding and magnet arrangements so that its longitudinal axis is at least substantially parallel to the longitudinal axes of said winding and magnet arrangements, and at least first and second yokes of ferromagnetic material and of such a configuration and arrangement that with the core means they form a return path arrangement of defined magnetic resistance for the magnetic flux which passes through the casing means. 
     
     
       37. A machine as set forth in claim 36 wherein said yokes are fixedly connected to the core means and the core means is connected to the assembly comprising the winding arrangement and the magnet arrangement immovably at least in the direction of said relative linear movement, wherein further the casing means surrounds the yokes and is separated from them by gaps which permit a relative movement of the casing means and form a lower level of magnetic resistance than the gap which passes through the casing means. 
     
     
       38. A machine as set forth in claim 35 wherein that at least one gap in the casing means is filled with a solid material of low magnetic permeability, which with parts of the casing means which are of ferromagnetic material forms an overall body with continuous internal contures. 
     
     
       39. A machine as set forth in claim 35 in the form of an electrical motor. 
     
     
       40. An electrical motor assembly comprising at least first and second electrical motors as set forth in claim 39, including means for connecting all the winding and magnet arrangements together immovably at least in the direction of the relative linear movement, wherein said casing means which at least partially comprises ferromagnetic material is common to the motors, the casing means having a gap for each motor, and means for actuating the winding arrangements such that the forces occurring between the winding and magnet arrangements of each motor and the common casing means act in the same direction to produce a relative linear movement. 
     
     
       41. An assembly as set forth in claim 40 including a core common to the electrical motors and including a plurality of yoke means of which at least one is associated with the first and second electrical motors. 
     
     
       42. A machine as set forth in claim 14 or 21 or 28 or 35 wherein the axial length of the magnet arrangement is at least substantially equal to the axial length of the winding arrangement. 
     
     
       43. A machine as set forth in claim 14 or 21 or 28 or 35 wherein both the winding and the magnet arrangements are each in the form a straight hollow cylinder of circular inside and outside cross-sections and wherein the longitudinal axes of the winding arrangement and the magnet arrangement coincide. 
     
     
       44. A machine as set forth in claim 14 or 21 or 28 or 35 wherein the winding arrangement surrounds the magnet arrangement. 
     
     
       45. A machine as set forth in claim 14 or 21 or 28 or 35 wherein the magnet arrangement surrounds the winding arrangement. 
     
     
       46. A machine as set forth in claim 14 or 21 or 28 or 35 wherein said magnet arrangement is formed by permanent magnet means. 
     
     
       47. A machine as set forth in claim 15 or 22 or 29 or 36 wherein the thickness of material and shape of the core, the yoke means and the casing means in the various cross-sectional regions are so matched to the magnetic flux which passes through the respective cross-sectional region at the maximum that saturation is avoided with the minimum requirement requirement of material. 
     
     
       48. An electrical machine as set forth in claim 14 or 21 or 28 or 35 in the form of an electrical generator.